Abstract : Diabetes mellitus is a pandemic disease that has struck each and every corner of the world. It is a chronic disease caused by inherited/ acquired deficiency in insulin production or in effectiveness of insulin produced. A wide range of oral antidiabetic drugs such as sulphonylureas, biguanides, Alpha glucosidase inhibitors, thiazolidinediones, meglitinides and the most recently introduced dipeptidyl peptidase-4(DPP-4) inhibitors have been used. The present article reviews various prescribing pattern studies of drugs conducted all over country and abroad. It was observed in the majority of such studies that physicians do not adhere to the guidelines made by regulatory agencies leading to irrational use of medicines. This in turn leads to increased incidence of treatment failure and economic burden on the patient and the community as a whole. The treatment of diseases by the use of essential drugs, prescribed by their generic names, has been emphasized by the WHO and the National Health Policy of India. We conclude that the prescribing pattern studies provide a bridge between areas like rational use of drugs, pharmacovigilance, evidence based medicine and pharmacoeconomics. In India, this is the need of the hour to utilize the data generated by so many prescribing pattern studies done in every state and on every drug, so that the main aim of promoting rational use of drugs is fulfilled.